Electrical interrupter



1, 21, March 22,1927. A. LEIGHTON 6 673 ELECTRI CAL; I NTERRUPTER Filed April 23. 1926 m j II Patented Mar. 22, 1927.

PATENT OFFICE.

UNITED STATES ALAN LEIGHTON, OF WASHINGTON, DISTRICT 0F COLUMBIA, ASSIGN'OR TO THE GOV- ERNMENT AND THE PEOPLE OF THE UNITED STATES OF AMERICA.

ELECTRICAL INTERRUPTER.

Application filed April 23, 1926.

(GRANTED UNDER THE ACT 01* This application is made under the act of March 3, 1883, Chapter 1&3 (22 Stat. 625) and the invention herein described and claimed may be used by the Government of the United States or any of its otficers or employees in the prosecution of work for the Government, or by any citizen of the United States, without payment to me of any royalty thereon.

This invention relates to an instrument designed to open and close automatically an independent electric circuit by the opening and closing of a portion of another circuit. The instrument action depends upon the arrangement and mutual interaction of three bar electromagnets with the accompanying electrical circuits.

My apparatus depends not only upon the attraction of a magnet for iron in its action but also upon the fact that like poles of magnets repel each other while dissimilar poles attract. This is the feature new to the interrupter and relay work. The relative positions of the magnets together with the system of wiring which permits of the presentation to each other of suitable polarities as required for the operation of the interrupter-relay are also new.

In the drawing, Fig. 1 represents a front elevation of the entire apparatus and Fig. 2 shows a side elevation of the same.

Referring to the drawing it will be seen that the apparatus consists essentially of three electromagnets of the bar typeA, B, and C, supported on a base X by means of plates H, H and L respectively. The electromagnets A and B have reduced upper ends I and I which are held in position on plates H and H by means of nuts 1 The magnitude of the movement of the electromagnet C is controlled by stops N at either end of and below the electromagnet C, which stops are secured to the base X by plates M. The stops are adjustable upwardly and downwardly. The magnet C, tree to move about a center pivot K, is placed opposite to and perpendicular to the poles of magnets A and B, as shown. The contacts of the circuit to be controlled are located at D; the binding posts are at E and E. The magnets A and B are wound in series in such a way that when current is flowing they each present the same pole to Serial No. 104,233.

MARCH 3, 1883; 22' STAT. L. 625.)

magnet C. Magnet B is wound to have a strength about three or four times as great as A. Magnet B has a soft iron core, as

does. C. Magnet A, however, has a steel core and will always contain considerable residual magnetism. The terminals of these magnets are at G and G. Magnet C is shunted across the other magnets, is wound to have about the same strength as the two others combined, has the controlling switch r regulator 0 connected in circuit with it, F and F, and is polarized so that the end under B has the polarity of B when current is flowing.

It is apparent that the residual magnetism in A will always draw the end of magnet C towards it when no current'is passing through the windings of the magnets, and that under these conditions the contact at D will always be broken. As soon as a current passes through A and B, however, B by its superior strength attracts its end of magnet C against the force of A and contact is made at D. New magnet O is so wound, as I have stated, that when the circuit through it is closed it is magnetized so that the pole under B has the same polarity as B and is repelled by it. Contact at D is thus broken by the combined forces of all the magnets. As soon as the circuit is broken, C becomes demagnetized, and B, by its superior strength as compared with A, closes the controlled circuit. If the operating circuit tails, both B and G are demagnetized; the residual magnetism in A breaks the contact D. The device thus guards against failure of the entire circuit, or failure of that portion of the circuit through magnets A and B, but of course does not guard against the failure of the operating switch itself.

This then is the operation of the interrupter. But there are a number of points which at once become obvious. The action is very positive on both the make and break of the controlled circuit. The force of the make and break may be varied through a wide range by suitable magnet design. The contact immediately swings to safety it the operating circuit is interrupted, or if magnets A and B become inoperative. The interrupter will operate on both direct and al ternating currents. It alternating current is to be used the core of magnets B and C must helaminated to prevent undue heating. In the experimental relay constructed by me a 12 ohm coil of No. copper wire was wound on the permanent magnet; With the passage of .05 amperes the heating was not excessive. If direct current is used the apparatus may operate through a resistance on the power line operating the controlled circuit, the magnets may be operated onan auxiliary circuit or the magnet C may operate alone on this auxiliary circuit. The windings of the magnets may be varied to suit the voltages available for these circuits. If alternating current is to be used it may be taken from the power line operating the controlled circuit through a resistance or an auxiliary source of power can be used. The

magnet C, however, cannot be operated independently of magnets A and B unless this power source is in phase with that operating A and B.. The positive make and break at the contact Dreduces to a minimum the danger of the contact points becoming frozen. The contact arm, if made of spring material will result in obtaining at the contacts the so-called wiping action found in telephone switch jacks. This also reduces to a minimum the danger of freezing. By thesuitable adjustment of stops to control the movement of the magnet C and the adjustment of magnets A and B with regard to C, and the suitable adjustment of contact D the contact can be made neaneva to open through a fairly wide arc. reducesthe danger of freezing.

It the apparatus is used as a relay the contact D maybe removed to the opposite side of the contact arm or magnets A and Bmay be interchanged. When in this position contact will be made when current passes through magnet O, and broken when it ceases.

I claim: V

An electrical interrupter, comprising two stationary electromagnets, a movable electromagnet supported in position opposite the two stationary electromagnets, the two stationary electromagnets wired so as to present the same magnetic poles to the movable electromagnet the movable electromagnet carrying a contact arm for the making and breaking of a controlled circuit, the wires of the controlling circuit being suitably shunted across the wires of the stationary electromagnets, the movable electromagnet raving one pole that corresponds magnetically to the pole of one of the stationary electromagnets and having another pole that is opposite magnetically to the pole of the This also other stationary electromagnet, and the sta-.

tionary electromagnet that has apole corresponding to the pole of the movable electromagnet possessing greater strength than the other stationary electromagnet.

ALAN LEIGHTON. 

